Factors Affecting the Regioselection of the Allylic Imidates Iodocyclization

Article abstract of DOI:10.1021/jo00375a027

The regiochemistry of thr iodocyclization reaction of allylic imidates leading to 4,5-dihydro-1,3-oxazoles or to 4,5-dihydro-1,3-oxazines strongly depends on the configuration of the double bond: (E)-allylic imidatesafford preferentially 4,5-dihydro-1,3-oxazines through a 6-endo closure, whereas (Z)-allylic imidates afford preferentially 4,5-dihydro-1,3-oxazoles through a 5-exo closure.Furthermore a study on the effect of an oxygen atom vicinal to the double bond is reported.